Disposable syringe



Feb. 14, 1950 I A. E. SMITH 2,497,562

DISPOSABLE SYRINGE Filed Aug. 4, 1947 INVENTOR Patented Fein. i4,y QSV UNITED STATES PATENT 0F FfCE msPosABLE snmNGEl Arthur; n.1. smith, Los Angeles, Calif; Application august 4, 1947', senat No. 766.02m 5..,craimsr, (c1. 12s-22o)l 'Ihzis ini/entier,1l relates, to disposable syringes;

The: general.` object.. Ot the, inventionl is to pro,- vdearl: improved- Syringe which. is useful for-the injection ot; medicina-l preparations..

A. more specific obieet or. invention ist to pmi/ide; a novell: plunger ion use in a. disposal syringe.

Another; -objectnf theinventionpisito provide; a novell needle member forl use; in` a hypodermic syringe.

Further: objects and;` adyantages ,of/myy invert: tions will; be apparentifrom: thefollowing. descr-'1ption, taken, in. connection with. theaccornpanying drawings; wherein.

. L ,is al side,x elevation. of asyringeshowing myv invention;

FigN 2. isk an extended side elevation. showing. the.. parts: constituting: syringe;l f

Fig... 3'.` isa an en'largedfr fragmentary, central-sectional view showingfmyfsyringe:

Fig. tV a, fragmentary view showing the end of the plunger when thesyringeis ready for use, and

Fig.. 5Iv is. an., enlarged., sectionv taken on, line -5, Fig. 3.

Referring tothe drawingiby reference characters, I have' shown my'inventionas embodied in a syringe indicated generally-'Y at I0. As; shawn thesyringe includes a.vcylindnical'y ampule; 0,122 nell.- t I whichl maybe vmadeof plastic. A517092@ I2, which may be made of rubber, is mounted in one end of the ampule. The stopper includes a projecting flange I3 and has an inwardly directed recess I4 and an outwardly directed recess I5 with a diaphragm I6 between the recesses.

The syringe includes a plunger, which is indicated generally at I1. The plunger includes a body I8 which is a cylindrical tube and may be made of transparent plastic or similar material.

In the ampule I arrange a cylindrical piston stopper which has a bulbous front end 2I and is recessed as at 2'2 at its inner end.. At its outer end the stopper 20 has a recess 23 which is threaded with threads 23' which have steeply inclined forward faces 24 and rear faces 25 which are substantially perpendicular to the axis of the stopper.

On the plunger tube I8 I arrange a front member which includes a tapered tip 3| and a projecting flange 32, the latter being adapted to be grasped by the fingers of the operator.

The front member includes an annular groove 33 which receives the forward end of the plunger body I8, as shown in Fis. 3` The front member 2i, includes aL bore 3,4; which includes enlarged recess a5.y i-nterme,diatel-A the.- lengtlt of the; bore. The; recess; 35.1 is preferably of a general cubical shape.

A, hypodermic needle.- :it` is: arranged in,K the here 341l andl'ias v aesubstantially" cubical pretube-rance 3 1; which. isz. arranged in; the", recess 35. rEhe 1 needle; includes@ pointed` forward vtip 3,15 and the needle'y extends; rearwardly. from, thegfront member and at its. extreme, reali' end.I is sharpcned@ as. at; 38p. Secured.E upon;` the, needleI ast by brazing, I; show: a; threaded member 3,9.4 The threads: 4imon: the member 319,` have, the;y same shape as the threads-l 2:3.

use'.L the Stoppers I2 and Zilfarel arrangediin the; anapule in; close-together; relatiensloi-p.l and a hypodermic needle is then.insertedl-- throughthe diaphragml lltand; the materialitofbef:injectedlis intoV the ampule tlms; forcing; the'.4 piston stopper 2:0; away from.v the stoppen I2f... When ,the desired; amount of. materia-l isf-:inthe ampule: the needles is; withdraw/fn;V frnm-- the diaplrlragzm` I5 `and the holethrouglr which the needles. passed:` is sealedl d-ue tothe: resiliency. ofs'the; materiale. The plunger' bodyr tit is then: insertedainlthetfoitward portion of 'tl-1e amp-ulean'cl. thel tlzn'eaidsa` ML are engaged with the threads 23 andrtlsre,` frontrmem.- ber 30 is: rotated',vv causing"theplungwbodyf I8 to mov-cinto the ampule; The.-.movemenlta.con. titanes untifli'thefendfof the.y tip 381i is closely adsjacer-itt'og4 but doesi not'enter; the diaphragml and the parts assume the position shown in Fig. 3. A exible, preferably transparent, sleeve 45 is then placed over the needle 31 and is engaged by the tapered tip 3| to maintain the needle 31 in sterile condition.

When the syringe is to be used, the front member 3o is turned relative to the ampule II to cause the threads 40 to further advance along the threads 23' so that the tip 38 punctures the diaphragm 26 and places the contents of the ampule in communication With the needle 36. When this occurs the forward end 42 of the piston stopper engages the rear end 43 of the plunger body I8 and the syringe is then ready for use.

In use the tip 45 is removed and the plunger is rotated t0 place the syringe in working condition, as described, and the injection is made. The plunger is slightly advanced and is then withdrawn to determine by the absence or presence of blood in the ampule whether a blood vessel has been pierced. If blood is present, indicating that a blood vessel has been pierced, the

3 needle is withdrawn and re-inserted properly and the injection is made.

From the foregoing description it will be apparent that I have invented a very simple and effective hypodermic syringe which can be economically manufactured and readily maintained sterile and wherein the syringe may very readily be prepared for use.

Having this described my invention, I claim:

1. A syringe comprising a cylindrical, transparent ampule anda plunger, a closure for one end of the ampule, said plunger including an elongated body, a threaded piston movable in the ampule, said plunger having a bore therethrough, a hypodermic needle disposed in said plunger bore, and a threaded member on said needle, the threads on said piston engaging said needle threaded member threads.

2. A syringe comprising a cylindrical, transparent ampule and a plunger, a closure for one end ofthe ampule, said plunger including a `cylindrical body, a threaded piston movable in the ampule, said plunger having an axial bore therethrough, a hypodermic needle disposed in said plunger bore, and a threaded member on said needle, the threads on said piston engaging said needle threaded member threads, said plunger having a front member thereon, said front member having an axial bore, said needle extending through said front member bore.

3. A syringe comprising a cylindrical, transparent ampule and a plunger, a closure for one end of the ampule, said plunger including a cylindrical body, a piston movable in the ampule, said plunger having an axial bore therethrough, a hypodermic needle disposed in said plunger bore, a threaded member on said needle and threads on said piston engaging said needle threaded member threads, said plunger having a front member thereon, said front portion including a projecting. tapered tip, said front portion having a nger engaging ange, said front member having an axial bore, said needle extending through said front member bore, said needle having a rectangular protuberance thereon, said front member having a recess receiving said protuberance.

4. A syringe comprising a cylindrical, transparent ampule and a plunger, a closure for one end of the ampule, a piston in the ampule, said piston having a threaded recess, a diaphragm closing the inner end of said recess, said plunger having an axial bore therethrough, a hypodermic needle disposed in said plunger bore, a threaded member on said needle, the threads on said piston engaging said needle threaded member threads, said plunger having a front member thereon, said front member having an axial bore receiving said needle, said needle projecting beyond said front member, the inner end of said needle having a pointed tip arranged in said piston recess and movable when the plunger is rotated relative to the piston to pierce the piston diaphragm to thereby place the needle in communication with the interior of the ampule.

5. A syringe comprising a cylindrical, transparent ampule and a plunger, a closure for one end of the ampule, said plunger including a cylindrical body, a piston in the ampule, said piston having a threaded recess, a diaphragm closing the inner end of said recess, said plunger having an axial bore therethrough, a hypodermic needle disposed in said plunger bore, a threaded member on said needle, the threads on said piston engaging said needle threaded member threads, said plunger having a front member thereon, said front member including a projecting tip, said front portion having a nger engaging-flange, said front member having an axial bore receiving said needle, said needle projecting beyond said front member, the inner end of said needle having a pointed tip arranged in said piston recess and movable when the plunger is rotated relative to the piston to pierce the piston diaphragm to thereby place the needle in communication with the interior of the ampule, said needle having a rectangular protuberance thereon, said front member having a recess receiving said protuberance, and a flexible cap engaging said tip and surrounding said needle, said cap having a hole receiving the end of said needle.

ARTHUR E. SMITH.

REFERENCES CITED The following references are of record in the iile of this patent: Y

UNITED STATES PATENTS Number lName Date 1,499,592 Spahlinger July l, 1924 '2,102,704 Hein Dec. 2l, 1937 

